1. Field
Multipath mitigation can be performed in a surface environment by various systems and methods. For example, antenna beams from multiple antennas can be used to reduce the impact of multipath on a received signal.
2. Description of the Related Art
Many aircraft systems receive Automatic Dependent Surveillance-Broadcast (ADS-B) position, velocity, and identification messages on the ground. Such messages can provide situational awareness and alerting for traffic on runways and taxiways. For example, see RTCA DO-260B (the content of which is hereby incorporated by reference) for more information about ADS-B systems. These systems can experience multi-path signal geometry paths that result in loss of ADS-B signals due to a nulling of signal or due to overlapping that occurs due to reflected signals from the ground or from other object reflective surfaces like buildings. Specifically, in certain environments, both an original signal and a multi-path signal can appear to a receiver with similar amplitudes, thereby either cancelling or otherwise interfering with one another.